Volumetrical pump



J. DELSUC Aug. 26; 1969' VOLUMETRICAL PUMP 2 Sheets-Sheet 1 Filed March 21. 1967 1v ousuc w 5 7 E A v M R o T T W 3 b w w P g- 26, 1969 J. DELSUC 3,463,091

VOLUMETRICAL PUMP Filed March 21, 1967 2 Sheets-Sheet 2 IAJVEIVTOK BTTOKNEI!) United States Patent US. Cl. 103-431 8 Claims ABSTRACT OF THE DISCLOSURE The volumetrical pump comprises a fixed casing provided with an annular recess containing a fixed radial partition and having an inlet port on one side of said partition and a moving cylinder assembly consisting of a ring provided with a radial slot and lodged within said recess with the partition extending through the slot and of a plate fixed to the ring and provided with outlet ports located on the other side of the partition, said plate sealing one side of the recess except for the outlet ports, the moving cylinder being supported by an eccentric bush carried by a rotary shaft whereby the rotation of said shaft causes the pumping of the fluid.

The present invention has essentially for its object a volumetrical pump of the type comprising a body provided with an annular hollow space including a radial partition and, in the vicinity of said partition, a port communicating with the suction channel of the fluid, a chamber contiguous to said hollow space and a propulsing cylinder assembly fitted upon an eccentric bush carried by a rotating shaft, said cylinder assembly comprising a ring provided with a slot and travelling within said annular hollow space as well as a plate perpendicular to said ring and isolating said hollow space from said chamber.

In the known pumps of the aforementioned type, the fluid discharge channel opens in the annular hollow space, likewise to the suction channel, but opposite to the latter with respect to the radial partition provided in this hollow space. In such a pump, the ring of the propulsing cylinder assembly determines, with the two concentric walls of the annular hollow space, spaces the volume of which successively increases and decreases during the circular translatory motion performed by said propulsing cylinder assembly, achieving thus the suction and the discharge of the liquid. The ring of the propulsing cylinder assembly operates like a distributing slide valve and connects the suction and discharge ports with these spaces.

In the pumps of this known type, the fluid to be pumped is in a direct contact with the drive mechanism of the pump, a particular result of this is that the packing of the shaft, which is a very sensitive member, comes also in contact with this fluid to be pumped. Moreover, this packing functions under the discharging pressure of the pump.

The pump according to the invention is characterized in that the fluid discharge channel opens into the aforementioned chamber, some orifices being provided through said plate, opposite to the aforementioned suction port with respect to the partition, in such way as to permit passage of the fluid flow from the suction channel to the discharge channel.

The actual fact of replacing the discharge port opening into the annular hollow space by a number of orifices provided in the propulsing cylinder assembly allows a substantial simplification of the moulded part, wherein said annular hollow space is contrived, as this part then comprises nothing else but the suction port.

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According to another feature of the invention, the aforementioned plate includes two orifices placed on both sides of the aforementioned ring and close to the slot of said ring.

According to a further characteristic of the invention, the aforementioned cylinder assembly is removably secured on a sleeve or the like, the latter being rotatively set up on the aforementioned bush.

This removable arrangement allows an easy assembly and disassembly of the cylinder assembly, and hence a ready cleaning of the pump.

According to a still further feature of the invention, a fluid-tight diaphragm is provided between the aforementioned sleeve and the body of the pump, this diaphragm being housed within a bore or the like of said body wherein the fluid suction channel opens and which communicates with the suction port of the annular hollow space in such way as to isolate the fluid from the drive mechanism of the propulsing cylinder assembly.

This diaphragm, which completely isolates the liquid to be pumped from the mechanical portion of the pump, allows to the drive mechanism of the pump and especially to the packing to function in a lubricant.

Besides, it is easy to perceive that the diaphragm and the packing of the shaft function under the suction pressure of the pump. The resistance as well as the fluidtightness of this diaphragm and of this packing are the more eflicient as the pressure to which they are subjected is lower.

This diaphragm allows also to reduce to a minimum the number of the components moving with friction within the liquid to be pumped, as in this liquid to be pumped subsists only the friction of the ring against the walls of the annular hollow space.

The presence of this diaphragm allows besides to obtain a complete fluid-tightness of the pumping-circuit, this being an important advantage in the case where dangerous products, such as some liquefied gases, radio-active materials, etc., are to be pumped.

Other features of the invention will appear as the following description proceeds:

In the appended drawings given only by way of examples:

FIGURE 1 shows, in an axial cross-section, a pump according to a method of embodiment of the invention;

FIGURE 2 is a plane view showing the portion of the pump illustrated on FIGURE 1; in this portion is contrived the annular hollow space receiving the ring of the propulsing cylinder assembly;

FIGURE 3 is a plane view showing the propulsing cylinder assembly of the pump illustrated by FIGURE 1;

FIGURES 4a to 41 represent, in a schematic way, the variations of the various spaces determined by the cylinder ring and the walls of the annular hollow space during the motion of the propulsing cylinder assembly.

In accordance with the form of embodiment represented on FIGURE 1, the volumetrical pump according to the invention comprises essentially a body 1, including a cylindrical bore 2, wherein opens the fluid suction channel 3a. On one of the end portions of this body (the right end portion when considering FIGURE 1) are mounted, on the one hand, a part 4 with a cylindrical configuration (see FIGURE 2) provided with a central orifice 5 and with an annular hollow space 6, and on the other hand, a flange or the like 7 which communicates with a fluid-discharge channel 3b. Consequently, the part 4 and the flange 7 determine a chamber '8, which makes up the discharge chamber of the pump.

The hollow space 6 includes a radial partition 9 and its bottom wall is provided with a suction port 10 with the shape of a curvilinear triangle located near the partition 9, this port allowing connection between said hollow space 6 and the bore 2 wherein opens the fluid-suction channel 3a.

The pump comprises beside a propulsing cylinder assembly designated as a whole by 11 (see FIGURE 3) and including a plate 12 and a ring 13 having as a center, perpendicular to this plate and provided with a slot 14 which corresponds to the approximate position of the fixed radial partition 9 of the annular hollow space. In its central portion, the propulsing cylinder assembly comprises a hub or the like 15, concentric with the ring 13, as well as two members 16a, 16b in the shape of segments of circles raised from the plate 12 back of hub 15 defining between them a cleft 17.

The plate 12 is provided with an opening 18 in the shape of a triangle presenting two curvilinear sides 18a and 18b. The curvilinear side 18a admits as a center the point 011 at a distance d from the center 0 of the propulsing cylindrical assembly, while the curvilinear side 18b admits as a center the point 0b, located opposite to 0a with respect to 0, at a same distance d from 0.

The plate 12 comprises besides a curvilinear notch 19 opening on the periphery of said plate, this curvilinear notch admitting the point 001 as a center.

The propulsing cylinder assembly 11 has its hub 15 fitted upon a sleeve or the like 20, supported by a bush 21 which itself is set up in an eccentric way on a shaft 22. This bush 21, which rotates together with shaft 22, is pulled by springs 23 which tend to give it a maximum eccentricity. A needle bearing 24 is inserted between bush 21 and sleeve 20. The shaft 22 itself is introduced, through the bearings 26, in an element 25 attached to the other end portion of body 1 (left end portion when considering FIGURE 1). A packing, designated as a whole by 27 and including two O-rings 27a and 27b, secures the fluid-tightness between the shaft 22 and the element 25.

The sleeve 20 is provided with a peg or stud 20a which is engaged in the cleft 17 of the propulsing cylinder assembly, the latter being hence installed in a removable way on this sleeve 20. A set of X-type cross-members, of a known type (not represented), forces the sleeve 20 and consequently the propulsing cylinder assembly 11 to perform a circular translatory motion. A spring 28, one end of which uses the semi-circular members 16a and 16b of the propulsing cylinder assembly as props, while its other end is housed in a recess 29 substantially co-axial with the shaft .22 of the flange 7, keeps the propulsing cylinder assembly pressed against the front side of piece 4, at least in the initial stage of the operation of the pump, that is to say when the discharge pressure is not yet suflicient to secure this support.

One end of a diaphragm 30 which has the shape of a cuff and is made of a resilient material, for example of rubber, is made solid of the body housing the device, while the other end of this diaphragm is attached to the sleeve 20 in such way as to separate the bore 2 in two -independent chambers, the one, external, 2a, communicating with the suction channel 3a, the other, internal, 2b, including the drive mechanism of the propulsing cylinder assembly. The end portion 30a of the diaphragm 30 is made solid with the sleeve 20 by means of an annular workpiece 31 fastened to said sleeve by screws 32, while the end portion 30b is made solid of the element 25 which itself is solid of body 1, by means of an annular workpiece 33 fastened by screws 34. The annular workpiece 33 is provided with a boundary lath 33a with a rounded shape, this lath permitting the free play of the diaphragm 30 during the motions of the propulsing cylinder assembly.

This diaphragm is arranged within the bore 2, that is to say toward the suction-side of the pump, and it escapes thus being subjected to the high pressures of the discharge. Moreover, this diaphragm isolates the drive mechanism of the cylinder assembly 11 as well as the packing 27 from pumped fluid. This mechanism and this packing function hence in a lubricating bath of oil.

When the shaft 22 rotates, it drives the eccentric bush 21 into rotation, the latter driving in turn the propulsing cylinder assembly 11 by means of the sleeve 20. The propulsing cylinder assembly performs a circular translatory motion during which its cylinder 13 remains internally tangent to the two concentric cylindrical faces forming the annular hollow space 6. The cylinder of the propulsing cylinder assembly and the 'internal and external cylindrical faces of the annular hollow recess determine spaces A, A, B, B (see FIGURES 4a to 41), the volume of which increases and decreases successively during the motion of the propulsing cylinder assembly which is driven into a circular translatory motion by the shaft 22 rotating following the arrow F. The suction of the fluid is accomplished through the port 10 which opens in the bottom wall of the annular hollow space 6 and which communicates with the channel 3a, while the fluid is discharged through the orifice 18 and the notch 19 provided on the plate 12 of the propulsing cylinder assembly 11, this orifice 18 and this notch 19 connecting, by certain positions of the cylinder assembly, the hollow space 6 with the discharge chamber 8.

On FIGURES 4a to 4], the spaces wherein the suction is performed have been represented with continuous section-lines (vertical or horizontal), while the spaces wherein the discharge is performed have been represented in dotted section-lines (vertical or horizontal).

For example, FIGURE 4a shows three spaces: A, wherein the suction is performed, the fluid penetrating through the port 10, B, wherein the discharge begins, the fluid being discharged through the orifice 18, and A, wherein the discharge is performed, the fluid being discharged through the notch 19.

On FIGURE 4b, the suction continues in A, and the discharge in B and A, while a new space B appears which is under suction.

On FIGURE 4c, A is still under suction and B under discharge, A has disappeared while B remains under suction.

On FIGURE 4d, the space previously designated as A starts now to discharge and is called A, While a new space A under suction appears; B is under discharge while B is under suction.

On FIGURE 42, A and B are under suction, B has almost disappeared while A is still under discharge.

Finally, on FIGURE 4 A is in suction, B has achieved its suction stage and is just passing into its discharge stage while A is still under discharge (hence, FIGURE 4 corresponds to a state of the pump, immediately before that represented on FIGURE 4a).

Quite obviously, the invention is by no means limited to the forms of embodiment described and illustrated, which have been given only by way of examples.

What I claim is:

1. A volumetrical pump with rotary drive comprising a stationary body including a bore communicating with a fluid suction channel, a hollow member secured on said body and having formed therein an annular cavity, a radial fixed partition in said cavity, an inlet port in said hollow member located in the vicinity of said partition and allowng communication between said cavity and said bore, a flange secured to said body, a chamber contiguous to said cavity and limited by said flange, said chamber communicating with a fluid discharge channel, a movable cylinder assembly comprising a ring provided with a slot for receiving the location of said partition and traveling within said annular cavity as well as a plate perpendicular to said ring and located in said chamber, said plate constituting a separating wall between said cavity and said chamber, outlet port means being provided through said plate opposite to said inlet port with respect to said partition, a rotating drive shaft extending through said bore, an. eccentric member mounted on said shaft for carrying said cylinder assembly and for imparting to the latter a movement of circular translation whereby rotation of said drive shaft will cause pumping of fluid from said fluid suction channel to said fluid discharge channel through said inlet port and said outlet port means.

2. A volumetrical pump as claimed in claim 1, wherein said outlet port means comprises an orfice which is located within said ring, said orifice having the shape of a triangle with two curvilinear sides, the two centers of said curvilinear sides bineg located on both sides of the center of said ring, at equal distance from said center.

3. A volumetrical pump as claimed in claim 2, wherein said outlet port means further comprises a curvilinear notch in said plate, said notch being provided outside said ring.

4. A volumetrical pump as claimed in claim 3, wherein the center of said notch is coincident with the center of that curvilinear side of the aforementioned triangle which is nearest to the center of said ring.

5. A volumetrical pump as claimed in claim 1, wherein said cylinder assembly is provided with a cleft and wherein a sleeve is provided between said eccentric member and said cylinder assembly, said sleeve having a peg engaging said cleft.

6. A volumetrical pump as claimed in claim 1, comprising a spring, housed in said chamber for pressing said plate against said hollow member.

7. A volumetrical pump as claimed in claim 6, wherein said flange is provided with a recess substantially concentric with said drive shaft and wherein said plate is provided with semi-annular members raised from the latter and substantially concentric with said ring, said spring having one of its ends housed in said recess and its other end engaged on said semi-circular members.

8. A volumetrical pump as claimed in claim 5 further comprising a flexible tubular sheath of impermeable material housed in said bore and surrounding said shaft, said tubular sheath having one of its ends fluid-tightly secured to said body and its other end fluid-tightly secured to said sleeve.

References Cited UNITED STATES PATENTS 1,459,637 6/1923 Poyet 103-130 1,906,142 4/1933 Ekelof 230-146 3,161,141 12/1964 Refson 103-132 3,307,489 3/1967 Eckerle et al.

FOREIGN PATENTS 467,050 1914 France. 829,554 1/ 1949 Germany.

KENNETH W. SPRAGUE, Primary Examiner 

